一个模块中有两个表单

我想在一个页面中修改两个表单。我用Doctrine生成了一个模块。我:

public function executeEdit(sfWebRequest $request)
  {
    $this->forward404Unless($news = Doctrine_Core::getTable('News')->find(array($request->getParameter('news_id'))), sprintf('Object news does not exist (%s).', $request->getParameter('news_id')));
    $this->form = new NewsForm($news);
  }

this works fine.

我补充说:

public function executeEdit(sfWebRequest $request)
      {
        $this->forward404Unless($news = Doctrine_Core::getTable('News')->find(array($request->getParameter('news_id'))), sprintf('Object news does not exist (%s).', $request->getParameter('news_id')));
        $this->form = new NewsForm($news);
        $this->forward404Unless($other = Doctrine_Core::getTable('Other')->findByNewsId(array($request->getParameter('other_id'))), sprintf('Object other does not exist (%s).', $request->getParameter('other_id')));
        $this->form = new OtherForm($other);
      }

，我得到这个错误:

 500 | Internal Server Error | sfException The "OtherForm" form only
 accepts a "Other" object.

我使用findByNewsId()

这工作正常-如果我使foreach，然后我有这些对象，但我不能在表单中显示它。我怎样才能做到这一点呢?